The Spectrum Of B&W

Let It Go! The spring flower displays at The Butchart Gardens on Vancouver Island, British Columbia, look like the grounds of a "Frozen" ice palace when captured in infrared using an IR-converted Canon EOS-1DS Mark II and EF 24-105mm lens. The exposure was 1⁄180 sec. at ƒ/16 with an ISO of 200. (Yes, we're grandparents to princesses.)

IR What I Am
I love the look of infrared photography; it's such an interesting black-and-white interpretation of landscapes. Digital sensors are especially sensitive to infrared light, which is invisible to us, but degrades color images. However, images perceived in infrared light alone can be extremely creative. Blue skies intensify to nearly black, foliage is rendered a ghostly white, and a full tonal range is present with unexpected black-and-white renderings based on original colors. I once captured infrared images with IR film, but in the digital age, there are more options: inexpensive post-capture software (faux infrared), external filters and, for those with true commitment, camera conversions.

Faux Infrared
Any RAW color image can be "converted" in post-capture software to approximate an IR look. Some images lend themselves well to this Photoshop exercise, while other images don't come close. It's hard to predict the end result, so you just have to experiment. Russ Burden's OP "Tip of the Week" article at www.outdoorphotographer.com/how-to/tip-of-the-week/bw-adjustment-layer-explore-infrared.html#.U5XSlijYMso uses an IR Adjustment Layer. If you're into nostalgia, Steve Patterson takes it all the way to approximate the look of the old IR film, with a bit of softness and grain, in his tutorial at www.photoshopessentials.com/photo-effects/infrared-photo/.

IR Filters
I've worked on my DSLRs with Singh-Ray's I-Ray infrared filter (www.singh-ray.com), which passes infrared wavelengths from 700nm to 1100nm, and Hoya's R72 and RM90 infrared filters (www.hoyafilter.com), which pass infrared rays above 720nm and 900nm, respectively. Place one of these very dark filters over your lens, and the only light that will reach the sensor will be IR wavelengths. If only it were that easy!

All of today's DSLRs and compact digital cameras have a filter over the sensor called a "hot mirror" or "cut-off" filter. Its purpose is to impede IR from getting to the sensor, which, as noted above, degrades a normal color image. In fact, some IR does get through, and because of this small amount of available IR, filters like the Singh-Rays and Hoyas will give you a real IR image. Be warned that the exposure will be long and a tripod will be necessary. With my Canon EOS 5D Mark III and an EF 24-105mm lens and the Singh-Ray I-Ray, I needed an ISO of 3200 and a 15-second exposure at ƒ/8. A Canon EOS 70D had identical exposure times. My colleague Robert Agli used a Nikon D800E and needed 15 seconds at ƒ/8 and an ISO of 800. These aren't recipes for quality images.

If you want better quality and more versatility in infrared capture, the best choice is a camera converted to specifically take IR.

Cameras Converted To Infrared
When a DSLR is converted to infrared, the hot mirror filter is removed, leaving the camera's sensor unprotected from, and extremely sensitive to, both IR and visible wavelengths of light. To get the pure IR image we're looking for, a new filter must be installed to block the visible light. The filter can be external, such as one of those mentioned above, or an internal replacement of the hot mirror filter. Now all the power of your DSLR can be brought to bear on creative IR imaging. Handheld IR captures with exposures such as 1⁄125 sec. at ƒ/11 are routine.

Not every lens works well with an IR-converted camera; some produce a hot spot in the center of the image. This is caused by internal reflections and interaction with certain lens coatings. The website LensPlay (www.lensplay.com/lenses/lens_infra_red_IR.html) lists the lenses that don't work well with IR. Nonetheless, a wide range of lenses work very well with IR conversions: The lenses I regularly use with my converted Canon EOS-1DS Mark II are the EF 17-40mm ƒ/4L, EF 24-105mm ƒ/4L and EF 100-400mm ƒ/4.5-5.6L. There are no hot spots in IR with these lenses. In our Nikon tests, we had major hot spots with the 24-70mm ƒ/2.8 using the Nikon D800E and a Nikon F4 using the Singh-Ray I-Ray filter, but we tested many other Nikon lenses with no problems.

Focusing infrared light can be a real problem because it's at a different wavelength than visible light. Older lenses may have a small red dot on the focusing barrel to indicate where to set the focus with IR light. Keep in mind that the focusing point changes with the focal length of the lens. This means that a zoom lens will have different focusing points with each focal length change. These changes are relatively small and I usually eliminate the problem by using an ƒ-stop of at least ƒ/11 to maximize my depth of field. Depending upon the type of camera you're using, the focusing problem can be completely avoided, so consider this issue when deciding which camera to convert to IR.

In the past, we'd recommend conversion of any DSLR that had been decommissioned because it had been replaced by the latest version of camera magnificence. It's time to rethink that advice. Any camera with Live View can be focused in IR accurately on the LCD because the image on the LCD in Live View is actually what the sensor is seeing. I'll add here a promotion for the Hoodman HoodLoupe (www.hoodmanusa.com), which allows you to see the camera's LCD screen in all light conditions. If you've already decommissioned a camera with Live View, that would be your IR conversion choice. If you don't have one of these gathering dust in the closet, look at a newer consumer-grade camera like one of the Canon Rebels or the Nikon 5100, 5200 or 5300 series. Pentax has the K-500 at under $600 with an 18-55mm zoom. The point here is to achieve a digital camera with Live View that will accept your regular lenses. The ultimate camera to convert would be a mirrorless full-frame, with a good electronic viewfinder (Sony's a7R).

Once you decide to convert a camera, there are a few more decisions to make. I recommend LifePixel (www.lifepixel.com/188.html) to do the work. They have converted several cameras for me, and their service and quality are top notch. (Note: I recommend equipment and companies in my column only when I've worked with them and have had success using their products.)

There are several IR filters from which to choose; each gives a different result. Check LifePixel's website for a photo demonstration of the results from each type. Here's a brief description of the differences.

Deep B&W IR—Longer exposure, most dramatic (830nm), no need to manipulate the camera result in Photoshop.

Standard Color IR—Some color with the IR (720nm), similar to the Hoya R72 IR filter.

Enhanced Color IR—More color in the sky and foliage (665nm); can be changed in Photoshop to match a standard IR filter.

Super Color IR—Vibrant foliage and sky of a different color than visible (590nm); more color to mess with and will match the deep black-and-white when worked on in Photoshop.

Super Blue IR—Passes blue light as well as IR, allowing saturated blue skies and an IR look straight from the camera; a little fringing because the blue and yellow focus at different points.

Full Spectrum Clear—Choose the look you want by putting filters in front of the lens—visible color, IR color or UV light; requires Live View because the viewfinder will be black (unless you have an electronic viewfinder that reads off the sensor).

More Than IR
You might think that shooting a lot of IR will be boring and that you won't use a converted camera enough to justify the expense. But I find that there are many ways to be creative with an IR camera. I've taken one with me on small planes and commercial flights. Huge cloud formations photographed in IR at 30,000 feet are really dramatic. IR also cuts haze. And I've done some interesting portraits with IR, especially when the subject is photographed amidst colorful clothing or foliage to make it clear that IR has been used. This is important because IR changes hair and eye color and skin tone in sometimes strange ways. I'm a fan of time-lapse movies: think of an IR time-lapse with dramatic foliage and even more spectacular clouds moving across an intense sky. If you convert a DSLR or compact camera that has a video capability, you can capture high-def IR video for a surprising and creative look.

My next project is to have a Live View camera converted to Super Blue so I can do weird time-lapses, crazy movies or even serious landscapes in a different light.

Follow George Lepp's exploits, see his latest photographs and be part of the discussion on his Facebook page: www.facebook.com/georgelepp.

One of North America’s best-known contemporary outdoor and nature photographers and a leader in the field of digital imaging and photographic education, Lepp is the author of many books and the field editor of Outdoor Photographer magazine. One of Canon’s original Explorers of Light, Lepp finds inspiration in advancing technology that fuels creative innovation and expression of his life-long fascination with the natural world.